Ford Repair: Ford 460 fuel problems, class c motorhome, aluminum plates

Question
I have a 1991 Class C motorhome with a fuel injected 460 engine. I had the fuel tank cleaned, pump replaced, catalitic converter replaced, fuel filter replaced all on the advice of mechanics. To solve a problem that seems like vapor lock when the air tempature outside is very hot.  I just read on the internet that ford was having problems with  fuel pumps in my year range that are in the gas tank.  I also recently covered my gas lines close to the engine with a heat shield.  I have not had the chance to try this solution out yet.  But I am at a lost to solve this problem.  Any advise would be great.

Answer
vapor lock can be a big problem on fuel injected motors.  I suggest installing a clear fuel filter near the engines so you can see if bubbles are accumulating in the fuel line.  Put the clear filter a close to the fuel rails as possible.  If vapor lock is the problem, trace the fuel lines and see where you think the heat is coming from and install heat sheilding, either aluminum plates or fiberglass cloth.